This invention relates to an ultrasonic diagnosis apparatus and, more particularly, to electronic scan type ultrasonic diagnosis apparatus including a signal transmission line using a reduced number of photo transmission lines between an ultrasonic probe and transmitting-receiving devices.
In conventional ultrasonic diagnosis apparatus, an ultrasonic probe and a transmitter-receiver are generally connected with individually shielded electric wires. Since electronic scan type ultrasonic apparatus has, for example, in the past had about 30 to 100 transducer elements in its probe, it needed 30 to 100 electric wires for actuating the transducer elements. Also, the configuration of the ultrasonic probe, including the electric wires, has been very difficult to deal with because it is impossible not only to decrease the diameter of each electric wire further but also to increase the lengths of the wires due to high frequency attenuation since the available scope of ultrasonic frequency is quite high, being about 1 to 10 MHz.
Moreover, in the transmitting of both the transmitting and receiving signals through the shielded wires, the metallic materials composing the wires become a receiving antenna for external electronic noise waves. As a result, the signals transmitted through the shielded wires are affected and the ultrasonic image displayed on a monitor is deteriorated. Additionally, since cross talk of about -40 dB exists between the shielded wires, it has been impossible to completely clear the displaying image on the monitor from interference when using shielded wires for the signal transmission line, even if other problems are resolved.